cve-2026-6331
LOW CVSS 2.1 cvelistv5
Description
HMAC zero-length tag forgery in EVP_DigestVerifyFinal, where a zero-length tag could be accepted as valid during HMAC verification. In the OpenSSL-compatibility HMAC verify path the supplied signature length was only checked as not exceeding the MAC length, so a zero-length or otherwise truncated tag could pass verification. The fix requires the supplied tag length to exactly equal the MAC length and rejects a zero-length MAC, so a forged short or empty tag is no longer accepted.
Timeline
- Published
- 2026-06-25 20:56 UTC
- Last Modified
- 2026-06-26
CVSS Details
- Attack Vector
- LOCAL
- Attack Complexity
- HIGH
- Privileges Required
- NONE
Affected Products
- wolfSSL wolfSSL
Weaknesses (CWE)
SSVC (CISA Stakeholder-Specific Vulnerability Categorization)
CISA Coordinator
v2.0.3
- Exploitation
none- Automatable
no- Technical Impact
partial- Decision timestamp
2026-06-26T13:52:52.624679Z
What is SSVC? — CISA's vulnerability-prioritisation framework using a decision tree rather than a single score.
References
Linked Vulnerabilities
No linked vulnerabilities found.
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Enrichment data
Aggregated bundle (all enrichments)